h1{
    width: 400px;
    height: 100px;
    padding: 50px;
    margin: 50px;
    border: 1px solid #ffccdd;
}

span{
    widows: 400px;
    height: 100px;
    padding: 10px;
    margin: 10px;
    border: 1px solid #00dddd;
}

/* div{
    display: inline;
}

a{
    display: block;
    width:100px;
    height:100px;
} */

a{
    display: inline-block;
    width: 200px;
    height: 100px;
    border:1px solid #cfcfcf;
}

a:hover{
    background-color: #0000cc;
}

div.box_before{
    width: 350px;
    height: 30px;
    background-color: chartreuse;
}

div.box{
    box-sizing: border-box;
    width: 350px;
    height: 150px;
    margin: 25px;
    padding: 25px;
    border: 5px solid black;
}

div.box.after{
    width: 350px;
    height: 30px;
    background-color: chartreuse;
}

div.box_outline{
    width: 500px;
    height: 300px;
    border: 2px solid blue;
}

div.box_size{
    width: 50%;
    min-width: 300px;
    height: auto;
    max-height: 100px;
    background-color: crimson;
}

div.box_margin{
    width: 300px;
    height: 100px;
    /* margin: 20px; */
    margin: 10px 20px 5px 5px;
    /* margin-top: 50px; */
    /* margin-left: 28px; */
    /* margin:0 auto; 水平居中 */
    /* margin-bottom: 50px; */
    background-color:darkorange;
}

div.box_margin2{
    width: 300px;
    height: 100px;
    margin-top: -40px;
    background-color:darkseagreen;
}

div.box_outline p{
    margin-left: 30px;
    width: 100px;
    height: 30px;
    border-left: 5px solid gold;
    border-top: 1px solid gold;
    border-bottom: 1px solid gold;
    border-right: 1px solid gold;
    /* padding-left: 5px;
    padding-top: 5px; */
    padding: 5px 0 0 5px;
}

div.box_outline p:hover{
    border-left: 5px solid gold;
}